Question: If Shimon claimed payment from Reuven after the set time, and Reuven said that he paid before the set time - what is the law?

Do we believe Reuven due to a Migo (if he wanted to lie, he could have lied better, and said that he paid on the set day), even though this opposes a Chazakah (that people do not pay before the set time)?

Or, do we not believe a Migo that opposes a Chazakah?

Answer #1 (Mishnah): We assume that both paid unless one can prove that the other did not.

Question: What is the case?

If Levi claimed payment after the time, and Yehudah says that he paid on the proper day, this is obvious!

Answer: Rather, Levi claimed payment after the time, and Yehudah says that he paid before the proper day;

This shows that we believe the Migo against the Chazakah!

Rejection: This case is different, for he cannot wait to pay. He owes him once each row of bricks is laid!

Answer #2 (Mishnah): If the wall was originally more than four Amos, neither can force the other to rebuild it more than four Amos;

If Reuven built it more than four, and Shimon built a wall near it... we assume that Shimon did not pay for it unless he can prove that he did.

Question: What is the case?

If Levi claimed payment after the time, and Yehudah says that he paid on the proper day, he should be believed!

Answer: Rather, Levi claimed payment after the time, and Yehudah says that he paid before the proper day;

This shows that we do not believe the Migo against the Chazakah!

Rejection: This case is different. Since he does not think that he must pay, he would not pay early.

Answer #3 (Mishnah): If Shimon claimed that Reuven owes him, and Reuven admitted, and Shimon demanded the money the next day:

If Reuven says 'I paid you', he is exempt;

If Reuven says 'I do not owe you', he is liable.

Suggestion: 'I paid you' means 'I paid on the day due.' 'I do not owe you' means 'I paid before the day due' (and he is not believed)!

Answer: No. 'I do not owe you' means 'I never borrowed from you';

That is like an admission that he never paid. (Since he admitted earlier that he did owe, he must pay.)

(Mishnah): ...If Shimon built a wall near it, he must share the entire cost of the wall (that Reuven built).

(Rav Huna): Building a wall close to half the wall is like building a wall near all of it (he must share the expense of the whole wall).

(Rav Nachman): He shares the expense only of the part of the wall that he built near.

Rav Huna agrees when a cornerstone was placed. (It shows that the wall will not be continued. He pays only for the part he built near.)

Rav Nachman agrees when holes were made in the wall for holding beams. (This shows that a second story will be added. He pays for the additional height.)

(Rav Huna): If Shimon built a tall wall dividing between his yard and Reuven's, holes (for holding beams) in a wall (on Reuven's side) are no proof that Reuven paid his share of the extra height, even if Shimon has boards near the holes to support beams;

Shimon can say 'I expected that you will later pay your share, and it would weaken the wall if the holes were made later.'

Version #1 (Rav Nachman): A Chazakah for (Reuven to rest) light beams (on Shimon's wall) is not a Chazakah for heavy beams. A Chazakah for heavy beams is a Chazakah for light beams;

(Rav Yosef): Even a Chazakah for light beams is a Chazakah for heavy beams.

Version #2 (Rav Nachman): A Chazakah for light beams is a Chazakah for heavy beams, and vice-versa.

Version #1 (Rav Nachman): A Chazakah for dripping (rainwater drips off Reuven's roof into Shimon's yard) is a Chazakah for gushing (a pipe collects the water, and it will gushes in one place). A Chazakah for gushing is not a Chazakah for dripping;

(Rav Yosef): Even a Chazakah for gushing is a Chazakah for dripping.

Version #2 (Rav Nachman): A Chazakah for dripping is a Chazakah for gushing, and a Chazakah for gushing is a Chazakah for dripping but not to drip off a roof of willow branches (for the drops are very close to each other.

(Rav Yosef): It is even a Chazakah to drip off a roof of willow branches.

Rav Yosef ruled in a case according to his teaching.

(Rav Nachman citing Rabah bar Avuha): If one rents an apartment in a big building, he may use the ledges and walls up to four Amos (Rashi - even past the length of his house; R. Chananel - up to a height of four Amos), where that is the custom;

One may not hang things on walls surrounding the special garden of the building.

(Rav Nachman himself): One may use walls of the special garden, but not the area in back of the building.

(Rava): One may even use in back of the building.

(Ravina): If Reuven placed beams (of a hut made for shade) on Shimon's wall, if they are there over 30 days and Shimon does not protest, Reuven has a Chazakah to leave them there permanently. (Rashi - we assume that he bought the rights to leave them there);

If he left a Sukah made for the Mitzvah until seven days (i.e. Sukos), he has no Chazakah. After seven days, he has a Chazakah.

If he fixed the beams with mud, he has a Chazakah immediately.

(Abaye): If Reuven and Shimon have houses on opposite sides of a Reshus ha'Rabim (public road) (which goes north-south), each makes a wall (four Amos tall) on the side of the roof facing his neighbor, more than half the length of that side. One builds on the north half, and one builds on the south half.

Question: Why is this only if a Reshus ha'Rabim is in between? The law should apply even to a private path!

Answer: It is a bigger Chidush regarding a Reshus ha'Rabim. One might have thought that Reuven can say 'I need not build, for even without me, you have no privacy due to people on the road!'

Abaye teaches that this is not so. Shimon can say 'they see me only by day. You see me also at night; '

Or, he can say 'they only see me when I stand. You see me even when I sit';

Or, he can say 'they see me only when they look. You see me automatically!'

Question: Why did Abaye teach that each builds on half his roof? This is obvious!

Answer: It is not obvious when Reuven built half a wall before consulting Shimon. One might have thought that Shimon can say 'finish the wall and I will share the expense';

Abaye teaches that this is not so. Reuven can say 'you didn't build it because you don't want the weight to weaken the wall of your house. Also I don't want a full wall for that reason!'

(Rav Nachman citing Shmuel): If Reuven's roof overlooks Shimon's yard, Reuven must build a four Amos wall on his roof;

If they have adjacent roofs, no wall is needed.

(Rav Nachman himself): A four Amos wall is not needed, but a ten Tefachim divider is needed.

Question: What does this divider do?

If for privacy, four Amos are needed!

If to prevent one neighbor from trespassing, even if he crosses a wall shorter than ten Tefachim, he shows himself to be a thief!

If it is due to goats or lambs, a divider that stops them from sticking their heads across suffices!

Answer: Really, it is to prevent trespassing. If he crosses a short wall, he could say 'I was retrieving something that I dropped';

He cannot claim this regarding a ten Tefachim wall.

Question (Beraisa): If Reuven's yard was above Shimon's roof, he is exempt.

Suggestion: He is exempt from building anything.

Answer: No. He need not build a four Amos wall, but he must build a ten Tefachim wall.

(Rav Huna): If Reuven's yard borders Shimon's yard, but is higher than it, Shimon builds below, until he reaches the level of Shimon's yard, and they build four more Amos together.

(Rav Chisda): Reuven must share the cost also of the wall below.

Support (Beraisa): If Reuven's yard borders Shimon's yard, but is higher, Reuven must share the cost of the wall below;

If Reuven's yard is higher than Shimon's roof, he is exempt.